Anesthetic efficacy of different doses of dexmedetomidine combined with ketamine in pediatric patients undergoing closure of ventricular septal defect / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the anesthetic efficacy of different doses of dexmedetomidine combined with ketamine in the pediatric patients undergoing closure of ventricular septal defect.Methods Ninety pediatric patients with ventricular septal defect requiring interventional treatment,aged 4-11 yr,weighing 12-47 kg,of ASA physical status Ⅰ or Ⅱ,were randomly divided into D1-3 groups (n =30 each) using a random number table.After admission to operating room,anesthesia was induced with iv atropine 0.02 mg/kg and ketamine 1.0 mg/kg,followed by administration of a loading dose of dexmedetonidine 0.5 μg/kg which was infused over 10 min.In D1,D2 and D3 groups,dexmedetomidine 0.7,1.0 and 1.2 μg· kg 1 · h-1 were infused intravenously,respectively,until the end of operation.After the pediatric patients lost consciousness,the femoral artery was punctured to perform interventional treatment.Additional ketamine 0.5 mg/kg was given when the depth of anesthesia was inadequate.BIS,BP,HR and SpO2 were recorded after admission to the operating room (T0),at 1 and 5 min after ketamine administration (T1,2),at the end of loading dose of dexmedetomidine infusion (T3),at 15 min after maintenance dose of dexmedetomidine infusion (T4),immediately after operation (T5),and immediately after emergence (T6).The total consumption of ketamine,cases who needed additional ketamine and atropine,operation time,emergence time and development of adverse effects such as respiratory depression and postoperative agitation were recorded.Results Compared with the baseline value at T0,BIS value was significantly decreased at T4,5 in the three groups,HR was decreased at T4,5 in D2,3 groups,and no significant change was found in BP and SpO2 at each time point in the three groups.Compared with D1 group,the requirement for additional atropine was significantly increased,the total consumption of ketamine was reduced,and the requirement for additional ketamine and incidence of respiratory depression were decreased in D2 and D3 groups.No patients needed additional ketamine in D2 and D3 groups.The requirement for additional atropine was significantly higher in D3 group than in D2 group.There was no significant difference in the operation time and emergence time among the three groups.No pediatric patients developed agitation during emergence from anesthesia.Conclusion Ketamine 1.0 mg/kg (for induction of anesthesia) combined with a loading dose of dexmedetomidine 0.5 μg/kg and maintenance dose of dexmedetomidine 1.0 μg·kg-1 · h-1 (for maintenance of anesthesia) can produce good anesthetic efficacy,which is an optimum combination of anesthesia in pediatric patients undergoing closure of ventricular septal defect.